I treat my girls to a mixed seed
a half cup twice a day for 5 hens. What they consume in 10 to 15 minutes. Feed too many treats will affect egg quality and quantity, I know, I doubled the amount of treats and egg production was less and shells were thinner. They have unlimited access to layers pellets and water.
My girls also free range for 2 hours before sunset,
to eat grass, clover, dandelion leaves and of course insects, 3 seasons of the year, when it's not raining. GC

Fruits, veggies, grass, weeds, berries, pumpkins, hard boiled or scrambled eggs, bread, pancakes, waffles. One day I gave them a slice of leftover bacon, that was the most fun to watch as they'd steal it from each other and run around with it.

Watermelon, meal worms, applesauce, peaches, cucumbers, and I like to do this thing where I cut up strawberries and differnst berries and put them in an ice cube tray and fill it with water and freeze it... they love it!!! But basically any fruit/vegetable they like!